1. Field of the Invention
The present invention relates generally to recording and/or playback apparatuses and methods suitable for a music server in which numerous music data are stored in a hard disk drive thereof and, more particularly, relates to a recording and/or playback apparatus and a method in which the stored data are protected even when the hard disk drive is changed.
2. Description of the Related Art
Music servers in which numerous music data are stored in a hard disk drive thereof have been proposed. Because of the fast access speed and large storage capacity of the hard disk drive, the numerous music data can be efficiently managed therein. A user selects desired music data from among those stored in the music server, and then the music server sends the selected desired music data to a portable recording/playback apparatus, whereby the selected desired music data can be easily played back at a place remote from the music server.
When the music data is stored on the hard disk drive, there is a possibility that the copyright of the music data may be violated due to illegal duplication of the music data. In order to prevent copyright violation due to illegal duplication, for example, the SCMS (Serial Copy Management System) may be adopted. SCMS prevents digital duplication beyond one generation when data is duplicated from one digital apparatus to another digital apparatus.
Input/output interfaces for hard disk drives are standardized, and the formats of file systems are generally standardized as well. Therefore, even though SCMS is adopted, when the hard disk drive is changed, the music data can be illegally duplicated.
As input/output interfaces of the hard disk drives used in digital apparatuses, IDE (Integrated Device Electronics) and SCSI (Small Computer System Interface) are standards and are widely used. The formats of file systems such as the DOS (Disk Operating System) file system and the UNIX file systems are generally standardized. Therefore, a hard disk drive which is connected to one digital apparatus and which has data stored therein using the digital apparatus can be removed from the digital apparatus, and then the hard disk drive can be connected to another digital apparatus, whereby the data can be exchanged between these two digital apparatus.
As long as music data is output via a regular digital audio output, SCMS prevents duplication of the data from being performed beyond one generation. However, when music data is output without using such a regular digital audio output, that is, when, as described above, the hard disk drive in one digital apparatus is changed to be connected to another digital apparatus, and the music data in the hard disk drive are duplicated to a storage media connected to the other digital device, SCMS cannot prevent this duplication. Accordingly, to deal with the above case, devices such as one disabling data to be read by digital apparatuses other than the original digital apparatus or one enabling data to become meaningless to the other digital apparatuses must be considered.
Recently, advanced cryptographic algorithms have been designed, and so-called cipher LSIs (large-scale integrated circuit) performing encryption or decryption on a signal have been developed. However, mounting of such a cipher LSI leads to high cost and is often inappropriate for civilian use. Protection of the copyright is desired without using so-called a cipher LSI and by applying a method which is as simple as possible.